It is the general practice in the medical community for medical waste, such as used hypodermic needles and syringes as well as testing vials, to be thrown into specially sealed red (to indicate hazardous waste) containers. The containers are periodically collected by a disposal service and dumped into huge disposal machines which pulverize and sterilize or incinerate the waste for further normal disposal such as in a landfill. Because of the gap in both time and distance between initial use and ultimate disposal, as well as the considerable expense involved, there is opportunity for abuse such as by illegal ocean dumping which has resulted in contamination of beach and fishing resources. To obviate such problems, various devices for the on-site destruction of used needles, syringes, vials and other medical wastes have been developed such as described in U.S. Pat. Nos. 3,683,733; 3,750,966; 3,785,233; 3,926,379; 3,929,295; 3,958,765; 4,269,364; and 4,971,261. However, many of these devices are of a very complicated nature making their cost, for desk top use, in many instances, prohibitively expensive. In addition, they are of varying degrees of effectiveness in fragmentation of particles to governmentally mandated size (i.e. capable of passing through a 1/2" sieve) since their portable size militates against continued heavy duty fragmentation. The portable size also prevents use of industrial type heavy duty motors such as used in large scale pulverizers. Accordingly, a significant problem with such devices is blade jamming, particularly in those devices used in a dry environment without processing or carrier fluids such as water or disinfecting solutions. The problem with blade jamming is further exacerbated by the nature of common medical waste which includes rubber and plastic from syringes, as well as metal needle elements, which resist fragmentation and shredding. With medical waste disposal devices, blade jamming is a particularly vexing problem since the system is sealed to prevent spread of infectious materials. It is also therefore very difficult to remove the material causing the jam, without compromising the safety of the device designed to prevent personal exposure to the hazardous infectious materials. Furthermore, while some of these devices are generally capable of performing fragmentation operations, they are not capable of effecting the more desirable finely comminuted pulverization, as in centrally located large disposal machines.